N06617 / W.Nr.2.4663 Special Alloys For Aerospace And Defense High Performance

High performance Alloy 617 (N06617, W.Nr.2.4663) semi-products for jet engines and aircraft gas turbine etc.

1 PRODUCT

High performance Alloy 617 (N06617, W.Nr.2.4663) semi-products for jet engines and aircraft gas turbine etc.

Alloy 617 is furnished in a wide range of standard mill forms including pipe, tube, sheet, strip, plate, round bar, flat bar, forging, hexagon, shaped section and wire, etc.

2 EQUIVALENT DESIGNATION

UNS N06617, NiCr23Co12Mo (EN), W.Nr. 2.4663, NiCr22Co12Mo9 (ISO), INCONEL® alloy 617, VDM® Alloy 617, Nicrofer 5520 Co, HAYNES® 617 alloy, CarTech® 617 Alloy

3 OVERVIEW

Alloy 617 is a solid-solution, strengthened, nickel-chromium-cobalt- molybdenum alloy with an exceptional combination of high-temperature strength up to 1100°C (2000°F) due to solid solution hardening and oxidation resistance. The alloy also has excellent resistance to a wide range of high temperature corrosion such as oxidation and carburization, and it is readily formed and welded by conventional techniques.

The high nickel and chromium contents make the alloy resistant to a variety of both reducing and oxidizing media. The aluminum, in conjunction with the chromium, provides oxidation resistance at high temperatures. Solid-solution strengthening is imparted by the cobalt and molybdenum.

4 APPLICATION

Typical applications are:

● Components for industrial and aircraft gas turbines, such as combustion cans, housings, turbine rings, and other parts exposed to high temperatures

● Air heaters

● Furnace muffles and radiant heater tubes

● High-temperature heat exchangers, valves and springs

● High-temperature gas-cooled nuclear reactors, such as the helium/helium intermediate heat exchanger for the high- temperature section of the nuclear process-heat prototype plant (PNP)

● Equipment for the chemical process industry (CPI), e. g. for the productions of styrene

● Pigtails and furnace tubing in the petrochemical industry

5 CHEMICAL COMPOSITION (wt%):

6 PHYSICAL PROPERTY

Density:ρ=8.4g/cm³ (0.303 lb/in³)

Melting temperature:1330-1380℃ (2430-2520°F)

Specific heat at 76°F (26°C): 0.100Btu/lb-°F (419J/kg-°C)

Electrical Resistivity at 78°F (26°C): 736 ohm-circ mil/ft (1.22 uΩ-m)

7 METALLOGRAPHY

Alloy 617 has a face-centered cubic structure with good metallurgical stability. Its excellent high-temperature strength is achieved by solid-solution hardening. The alloy is not age-hardenable.

8 CORROSION RESISTANCE

Alloy 617 exhibits excellent resistance to hot corrosion such as oxidation and carburization under static and cyclic conditions up to temperatures of about 1100°C (2000°F).

These properties, combined with outstanding mechanical properties, make this alloy especially suitable for high temperature applications.

Additionally the high contents of nickel, chromium and molybdenum contribute to the good overall corrosion resistance of alloy 617 in a variety of aggressive media.

9 OXIDATION RESISTANCE

The excellent resistance of alloy 617 to oxidation results from the alloy’s chromium and aluminum contents. At elevated temperatures, those elements cause the formation of a thin, subsurface zone of oxide particles. The zone forms rapidly upon exposure to high temperatures until it reaches a thickness of 0.001 to 0.002 in. (0.025 to 0.05 mm). The oxide zone provides the proper diffusion conditions for the formation of a protective chromium oxide layer on the surface of the metal. It also helps to prevent spalling of the protective layer.

10 MECHANICAL PROPERTIES

Alloy 617 has high mechanical properties over a broad range of temperatures. One of the alloy’s outstanding characteristics is the strength level it maintains at elevated temperatures. The resistance of the alloy to high temperature corrosion enhances the usefulness of its strength.

Typical room temperature mechanical properties of solution annealed material

11 WORKING INSTRUCTION

Alloy 617 has good fabricability. Forming, machining, and welding are carried out by standard procedures for nickel alloys. Techniques and equipment for some operations may be influenced by the alloy’s strength and work-hardening rate.

Hot forming

Alloy 617 has good hot formability, but it requires relatively high forces because of its inherent strength at elevated temperatures. In general, the hot forming characteristics of alloy 617 are similar to those of alloy 625. The temperature range for heavy forming or forging is 1850 to 2200°F (1010 to 1205°C) followed by water quenching or rapid air cooling. Light working can be done at temperatures down to 1700°F (925°C), followed by water quenching or rapid air cooling.

Heat treatment after hot working is recommended to obtain optimum properties.

For heating up workpieces should be charged into the furnace at maximum working temperature (solution-anneal temperature)

Cold forming

Cold working should be carried out on annealed material. Alloy 617 has a higher work-hardening rate than austenitic stainless steels.This should be taken into account when selecting forming equipment.

Interstage annealing may be necessary with high degrees of cold forming.

After cold reduction of more than 10%, or more than 5% for applications at temperatures above 900°C (1650°F) solution annealing is required before use.

Alloy 617 is readily cold formed by conventional procedures although its work-hardening rate, shown in Figure 1, is high. For best results, the alloy should be cold formed in the fine-grain condition, and frequent intermediate anneals should be used. Annealing for cold forming should be done at 1900°F (1040°C).

Figure 1 Effect of cold reduction on hardness

Heat treatment

Solution heat treatment should be carried out in the tempera- ture range 1150 to 1200°C (2100 to 2190°F). Water quen- ching is essential for maximum creep resistance. Below 1.5 mm (0.06 in.) thickness, rapid air cooling may be applied.

Stress-relief annealing may be performed at temperatures up to 870°C (1600°F).

For any thermal treatment the material should be charged into the furnace at maximum annealing temperature observ- ing the precautions concerning cleanliness mentioned earlier under ‘Heating’.

Machining

Alloy 617 should preferably be machined in the solution- treated condition. The alloy’s high work-hardening rate should be considered, i.e., only low surface cutting speeds with not too high a rate of feed should be selected. Tools should be engaged at all times.

An adequate depth of cut is important in order to cut below the previously formed work-hardened zone.

Cutting tools should be sharp and have positive rake angles to minimize work hardening of the material. Cutting feed and depth of cut must be sufficient to prevent burnishing of the workpiece surface.

12 STANDARD SPECIFICATION

For alloy 617, allowable design stresses for ASME Boiler and Pressure Vessel Code construction are defined in ASME Code Cases 1956 and 1982. Allowable design stresses for alloy 617 products are found in Table 1B of Section II, Part D of the ASME Boiler and Pressure Vessel Code.

Rod, Bar, Wire, and Forging Stock

ASTM B 166 / ASME SB 166 Rod, Bar and Wire

ASTM B 564 / ASME SB 564 Forgings

SAE AMS 5887 Bars, Forgings and Rings

VdTÜV 485 Sheet, Plate, Forging, Bar and Tubing

ISO 9724 Wire

DIN 17752 Rod and Bar

DIN 17753 Wire

DIN 17754 Forgings

Plate, Sheet, and Strip

ASTM B 168 / ASME SB 168 Plate, Sheet and Strip

SAE AMS 5888 Plate

SAE AMS 5889 Sheet and Strip

VdTÜV 485 Sheet, Plate, Bar and Tubing

ISO 6208 Plate, Sheet and Strip

DIN 17750 Plate, Sheet and Strip

Pipe and Tube

VdTÜV 485 Sheet, Plate, Bar, and Tubing

ISO 6207 Tubing

ASTM B 167 Seamless tube

ASTM B 546/ASME SB 546 Welded pipe

DIN 17751 Pipe and Tube

Composition

DIN 17744

EN 10302

VdTÜV 485

ISO 9722

13 COMPETITIVE ADVANTAGE:

(1) More than 50 years experience of research and develop in high temperature alloy, corrosion resistance alloy, precision alloy, refractory alloy, rare metal and precious metal material and products.
(2) 6 state key laboratories and calibration center.
(3) Patented technologies.

(4) Ultra-purity smelting process: VIM + IG-ESR + VAR

(5) Excellent high performance.

14 BUSINESS TERM